Have an Open Mind -- So the purpose of the above long preamble to ask you to have an open mind about the following research that was done and written up in a book from 1981.
Draw a Coffee Cup -- If you ask someone to draw a picture of a coffee cup, chances are they will draw something that looks like this:
Everyone Drew A Similar Picture -- In fact, a researcher named Palmer went all around the world and asked people to draw a coffee cup and the pictures above were what people drew. Notice the perspective of the cups. A few of them are "straight on", but most are drawn from a perspective as if you are slightly above the cup looking down, and offset a little to the right or left. This has been dubbed the "canonical perspective".
Why Not This? -- No one he studied drew this:
which is what you would see if you were looking at a coffee cup from way above and looking down. Of course not, you say, but.... why not? And if you are going to say that the first perspective is the one that we actually see most of the time, when we look at a coffee cup... that it is the angle we are used to seeing the cup on our kitchen tables, I will tell you that this research has been done on many objects. For example, people were shown pictures of horses from various angles and perspectives and they most quickly recognized it as a horse when it was from this same canonical perspective. Yet I am fairly sure that most of us have not looked at horses from above most of the time. And the research was done with people recognizing a very small dog or cat. The canonical perspective still won out, even though when we see cats or very small dogs we are mainly looking at them from high above, not just slightly above. In fact the research shows that when we imagine an object we imagine it from this canonical perspective.
So, Why Care? -- It seems to be a universal trait that we think about, remember, imagine and recognize objects from this canonical perspective. Why care? Well, if you want to use icons at your web site or in your web or software application that people will recognize, then you might want to use this perspective. This is probably not so critical if you are using a well known logo, for example, the logo for itunes or Firefox, but becomes important if the icon is not as familiar, such as recognizing below that one of the logos is of a truck, or a photo printer.
What Do You Think? -- Should we continue to use the canonical perspective?
And for those of you who like to read research:
Palmer, S. E., Rosch, E., and Chase, P. (1981). “Canonical Perspective and the Perception of Objects.” In Long, J., and Baddeley, A. (Eds.), Attention and performance IX, Hillsdale, NJ: Erlbaum.